The present invention relates to metal forming dies, and particularly to a guided keeper assembly and associated methods.
Metal forming dies, such as stamping dies and the like are well known in the art. Progressive metal forming dies are unique, very sophisticated mechanisms which have multiple stations or progressions that are aligned longitudinally, and are designed to perform a specified operation at each station in a predetermined sequence to create a finished metal part. Progressive stamping dies are capable of forming complex metal parts at very high speeds, so as to minimize manufacturing costs.
Heretofore, the dies used in metal forming presses have typically been individually designed, one of a kind assemblies for a particular part, with each of the various components being handcrafted and custom mounted or fitted in an associated die set, which is in turn positioned in a stamping press. Not only are the punches and other forming tools in the die set individually designed and constructed, but the other parts of the die set, such as stock lifters, guides, end caps and keepers, cam returns, etc., are also custom designed and individually installed in the die set. Current die making processes require careful machining, precision holes and recesses in the die set for mounting the individual components, such that the same are quite labor intensive, and require substantial lead time to make, test and set up in a stamping press. Consequently, such metal forming dies are very expensive to design, manufacture and repair or modify.
A modular guided keeper having a base with snap on mounting flanges which both precisely aligns the two die members, and positively limits the reciprocal travel therebetween would be clearly advantageous in simplifying metal forming die constructions and reducing the costs in designing, manufacturing and repairing the same. Positive retention of the base using snap-on flanges on an associated die member is important to ensure that the same does not loosen and cause damage to the die set and/or press, which would result in expensive repair and machine downtime.